cat is a command-line utility used to concatenate or copy the contents to standard output from a file or standard input (if no file name is passed).
cat is a command-line utility provided by GNU Coreutils which can be used to concatenate the content to standard output from a file or standard input (if no file name is passed).
To print the content of a file (let's say, ubuntu.txt), use:
cat ubuntu.txt
Details about the options/flags for cat can be found in the manpage.
On systems like MS-DOS that distinguish between text and binary files, cat normally reads and writes in binary mode. However, cat reads in text mode if one of the options -bensAE is used or if cat is reading from standard input and standard input is a terminal. Similarly, cat writes in text mode if one of the options -bensAE is used or if standard output is a terminal.[source]